Non-modulation is an intermediate phenotype of essential hypertension characterized by resistance to exogenous angiotensin II (Ang II) and by a strikingly increased family history of myocardial infarction. The purpose of the present protocol is to test the hypothesis that non-modulation is characterized by a relative state of glucose intolerance. This study aims to determine the relationship between glucose tolerance and the non-modulator phenotype in Caucasians and African Americans with essential hypertension.